How Do Obelia Reproduce?

Reproduction of Obelia medusae occurs sexually, eggs and sperm uniting to become small larvae surrounded by cilia . Although, beginning as a free moving individual, the larvae eventually settle, each one becoming the founding member of a new polyp colony.

What is metagenesis explain with life cycle of Obelia?

The correct option is B Metagenesis. Obelia shows alternation of asexual and sexual phases during its life cycle. The asexual phase is represented by the polyp while the sexual phase is medusa. The two alternate in the life cycle. Such an alternation between asexual and sexual phases is called metagenesis.

What is Obelia and characteristics?

Obelia Characteristics

Obelia is a very tiny marine hydroid with a height of 2 cm or a little more . The obelia’s body has two kinds of filaments which are vertical hydrocaulus and horizontal hydrorhiza. Obelia’s life cycle begins as hydroid polyps.

Which sequence reflects the life cycle of Obelia?

Structure of Obelia

Obelia throughout its life cycle takes two forms: polyp and medusa . The first form is diploblastic, two true tissue layers – an epidermis (ectodermis). In contrast, the second form is gastrodermis (endodermis), with a mesoglia which is jelly-like filling the area between the two tissue layers.

What is difference between polyp and medusa?

What is the function of Obelia?

The primary function of the medusa is sexual reproduction . Obelia is dioecious as each medusa has reproductive organs of only one sex.

What is the kingdom of Obelia?

What is the role of the medusae in the Obelia lifecycle?

The medusa, or jellyfish, swim freely and reproduce sexually, releasing eggs and sperm into the water . The resulting fertilized eggs develop into larvae, which attach to the ocean floor as new polyps.

Is sea anemone a polyp or medusa?

Sea anemones are examples of the polyp forms , while jellyfish are examples of the medusa forms. In the current classification, the Cnidaria phylum is divided into two major groups, Anthozoa and Medusozoa, based on the structure of polyps and the existence of a medusa stage in the life cycles (Fig.

Which of the following is a stage in the life cycle of Obelia a cnidarian?

1. Most cnidarians, such as Obelia, have life cycles that alternate between polyp and medusa generations. In Obelia, the most conspicuous stage is the polyp .

Why is Obelia trimorphic?

It is called trimorphic because it has 3 stages in its life and these are polyp medusa and blastostyle .

What is the habitat of Obelia?

Habit and Habitat:

Obelia is typically marine, colonial and sedentary . It is found attached on piles, rocks and sea weeds in shallow water. The polyp represents the asexual phase which is a prominent branched hydroid colony found attached to rocks, stones, shells of animals, wooden pilings etc.

How does Obelia eat?

Contrary to other Hydromedusae that are macrophagous, Obelia is a microphagous and filter-feeding medusa, at least at the onset of its medusan life. As Cnidaria evolved before their current metazoan prey, their ancestral diet was probably microphagous.

What does the word Obelia mean?

Definition of obelia

: any of a genus (Obelia) of small colonial marine hydroids with colonies branched like trees .

Is Obelia a jellyfish?

Obelia refers to a genus of sedentary colonial coelenterates with upright branching stems bearing minute cups in which the polyps sit while jellyfish refers to a free-swimming marine coelenterate with a gelatinous bell- or saucer-shaped body that is typically transparent and has stinging tentacles around the edge.

Is Obelia a polyp or medusa?

Obelia, genus of invertebrate marine animals of the class Hydrozoa (phylum Cnidaria). The genus, widely distributed in all the oceans, is represented by many species. The animal begins life as a polyp —a tentacled, stalklike form resembling a small sea anemone attached to the ocean bottom or some other solid surface.

Which is correct about polyp stage of Obelia?

Obelia is a genus in the class Hydrozoa, which consists of mainly marine and some freshwater animal species and has both the polyp and medusa stages in their life cycle and shows metagenesis.

Are polyp free swimming?

polyp and medusa, names for the two body forms, one nonmotile and one typically free swimming , found in the aquatic invertebrate phylum Cnidaria (the coelenterates).

Is a hydra a polyp?

Hydra are small polyps from 1 to 20 mm in body length . The body is crowned by up to 10 or 12 tentacles. Usually the tentacles are of approximately the same length as the body, but may be somewhat shorter, particularly in the green hydra, and can exceed 20 cm in length in hungry brown hydra in quiet water.

Is medusa free swimming?

The medusa is a free-swimming form ; it moves by rhythmic muscular contractions of the bell, providing a slow propulsive action against the water. The other principal body type of the adult cnidarian is the polyp, a stalked, sessile (attached) form.

What is Obelia and Aurelia?

Aurelia is genus of scyphozoan jellyfish , commonly called moon jellies . Obelia is a genus of hydrozoans , a class of mainly marine and some fresh water animal species that have both polyp and medusa stages in their life cycle .

How does a polyp turn into a medusa?

In organisms that exhibit both forms, such as members of the cosmopolitan genus Obelia, the polyp is the asexual stage and the medusa the sexual stage. In such organisms the polyp, by budding , gives rise to medusae, which either detach themselves and swim away or remain permanently attached to the polyp.

Who made me a princess Obelia?

Claude de Alger Obelia is a main character in Who Made Me a Princess and the current reigning emperor of the Obelian Empire. In The Lovely Princess, Claude executed Athanasia de Alger Obelia and usurped the throne by murdering Anastacius de Alger Obelia, his older brother and proper heir to the throne.